Vaccines

Moderna Vaccine

SPIKEVAX™ (elasomeran mRNA vaccine) is indicated for active immunization against coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus in individuals 12 years of age and older.


The current SPIKEVAX vial and carton labels have the product name 'COVID-19 Vaccine Moderna'.


The most powerful defense against disease has always lived within each of us: Our immune system.


And now, after a decade of research, Moderna is introducing mRNA-based technology that can unleash the immune system's ability to help fight disease like never before.


Pfizer Vaccine

The Pfizer–BioNTech COVID-19 vaccine, sold under the brand name Comirnaty, is an mRNA-based COVID-19 vaccine developed by the German biotechnology company BioNTech and for its development collaborated with American company Pfizer, for support with clinical trials, logistics, and manufacturing


It is authorized for use in people aged five years and older in some jurisdictions, twelve years and older in some jurisdictions, and for people sixteen years and older in other jurisdictions, to provide protection against COVID-19, caused by infection with the SARS-CoV-2 virus.


The vaccine is given by intramuscular injection. It is composed of nucleoside-modified mRNA encoding a mutated form of the full-length spike protein of SARS-CoV-2, which is encapsulated in lipid nanoparticles. Initial advice indicated that vaccination required two doses given 21 days apart, but the interval was later extended to up to 42 days in the US, and up to four months in Canada.


Flu Vaccine

Influenza vaccines — United States, 2021–22 influenza season*
Trade name (manufacturer) Presentations Age indication µg HA (IIV4s and RIV4)or virus count (LAIV4) for each vaccine virus (per dose) Route Mercury (from thimerosal, if present), µg/0.5 mL
IIV4 (standard-dose, egg-based vaccines†)
Afluria Quadrivalent (Seqirus) 0.25-mL PFS§ 6 through 35 mos§ 7.5 µg/0.25 mL IM¶
  0.5-mL PFS§ ≥3 yrs§td> 15 µg/0.5 mL IM¶
  5.0-mL MDV§ ≥6 mos§ (needle/syringe) 18 through 64 yrs (jet injector) 15 µg/0.5 mL IM¶ 24.5
Fluarix Quadrivalent (GlaxoSmithKline) 0.5-mL PFS ≥6 mos 15 µg/0.5 mL IM¶
FluLaval Quadrivalent (GlaxoSmithKline) 0.5-mL PFS ≥6 mos 15 µg/0.5 mL IM¶
Fluzone Quadrivalent (Sanofi Pasteur) 0.5-mL PFS** ≥6 mos** 15 µg/0.5 mL IM¶
  0.5-mL SDV** ≥6 mos** 15 µg/0.5 mL IM¶
  5.0-mL MDV** ≥6 mos** 15 µg/0.5 mL
7.5 µg/0.25 mL
IM¶ 25
ccIIV4 (standard-dose, cell culture–based vaccine)
Flucelvax Quadrivalent (Seqirus) 0.5-mL PFS ≥6 mos 15 µg/0.5 mL IM¶
  5.0-mL MDV ≥6 mos 15 µg/0.5 mL IM¶
HD-IIV4 (high-dose, egg-based vaccine†)
Fluzone High-Dose Quadrivalent (Sanofi Pasteur) 0.7-mL PFS ≥65 yrs 60 µg/0.7 mL IM¶
aIIV4 (standard-dose, egg-based† vaccine with MF59 adjuvant)
Fluad Quadrivalent (Seqirus) 0.5-mL PFS ≥65 yrs 15 µg/0.5 mL IM¶
RIV4 (recombinant HA vaccine)
Flublok Quadrivalent (Sanofi Pasteur) 0.5-mL PFS ≥18 yrs 45 µg/0.5 mL IM¶
LAIV4 (egg-based vaccine†)
FluMist Quadrivalent (AstraZeneca) 0.2-mL prefilled single-use intranasal sprayer 2 through 49 yrs 106.5–7.5 fluorescent focus units/0.2 mL NAS

Abbreviations: ACIP = Advisory Committee on Immunization Practices; FDA = Food and Drug Administration; HA = hemagglutinin; IIV4 = inactivated influenza vaccine, quadrivalent; IM = intramuscular; LAIV4 = live attenuated influenza vaccine, quadrivalent; MDV = multidose vial; mos = months; NAS = intranasal; PFS = prefilled syringe; RIV4 = recombinant influenza vaccine, quadrivalent; SDV = single-dose vial

About Flu
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Influenza (flu) is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and lungs. Some people, such as older people, young children, and people with certain health conditions, are at higher risk of serious flu complications. There are two main types of influenza (flu) viruses: Types A and B. The influenza A and B viruses that routinely spread in people (human influenza viruses) are responsible for seasonal flu epidemics each year. The best way to reduce the risk of flu and its potentially serious complications is by getting vaccinated each year.

Flu signs and symptoms usually come on suddenly. People who are sick with flu often feel some or all of these symptoms:

  • Fever* or feeling feverish/chills
  • Cough
  • Sore throat
  • Runny or stuffy nose
  • Muscle or body aches
  • Headaches
  • Fatigue (tiredness)
  • Some people may have vomiting and diarrhea, though this is more common in children than adults.

Can I get seasonal flu even though I got a flu vaccine this year?

Yes. It's possible to get sick with flu even if you have been vaccinated (although you won't know for sure unless you get a flu test). This is possible for the following reasons:

  • You may be exposed to a flu virus shortly before getting vaccinated or during the period that it takes the body to gain protection after getting vaccinated. This exposure may result in you becoming ill with flu before the vaccine begins to protect you. (Antibodies that provide protection develop in the body about 2 weeks after vaccination.)
  • You may be exposed to a flu virus that is not included in the seasonal flu vaccine. There are many different flu viruses that circulate every year. A flu vaccine is made to protect against the three or four flu viruses that research suggests will be most common.
  • Unfortunately, some people can become infected with a flu virus a flu vaccine is designed to protect against, despite getting vaccinated. Protection provided by flu vaccination can vary widely, based in part on health and age factors of the person getting vaccinated. In general, a flu vaccine works best among healthy younger adults and older children. Some older people and people with certain chronic illnesses may develop less immunity after vaccination. Flu vaccination is not a perfect tool, but it is the best way to protect against flu infection.

What side effects can occur after getting a flu vaccine?

While a flu vaccine cannot give you flu illness, there are different side effects that may be associated with getting a flu shot or a nasal spray flu vaccine. These side effects are usually mild and short-lasting, especially when compared to symptoms of flu. A flu shot: The viruses in a flu shot are killed (inactivated), so you cannot get flu from a flu shot. Some minor side effects that may occur are:
  • Soreness, redness, and/or swelling where the shot was given
  • Headache (low grade)
  • Fever
  • Muscle aches
  • Nausea
  • Fatigue
The nasal spray: The viruses in the nasal spray vaccine are weakened and do not cause severe symptoms often associated with influenza illness. In children, side effects from the nasal spray may include:
  • Runny nose
  • Wheezing
  • Headache
  • Vomiting
  • Muscle aches
  • Fever (low grade)
In adults, side effects from the nasal spray vaccine may include:
  • Runny nose
  • Headache
  • Sore throat
  • Cough
Vaccine Benefits

What are the benefits of flu vaccination?

There are many reasons to get an influenza (flu) vaccine each year. Flu vaccination is the best way to protect yourself and your loved ones against flu and its potentially serious complications. Below is a summary of the benefits of flu vaccination and selected scientific studies that support these benefits.
  • Flu vaccination can keep you from getting sick with flu.
    • Flu vaccination prevents millions of illnesses and flu-related doctor's visits each year. For example, during 2019-2020 flu vaccination prevented an estimated 7.5 million influenza illnesses, 3.7 million influenza-associated medical visits, 105,000 influenza-associated hospitalizations, and 6,300 influenza-associated deaths.
    • During seasons when flu vaccine viruses are similar to circulating flu viruses, flu vaccine has been shown to reduce the risk of having to go to the doctor with flu by 40 percent to 60 percent.
  • Flu vaccination has been shown in several studies to reduce severity of illness in people who get vaccinated but still get sick.
    • A 2021 study showed that among adults, flu vaccination was associated with a 26% lower risk of ICU admission and a 31% lower risk of death from flu compared to those who were unvaccinated.
    • A 2018 study showed that among adults hospitalized with flu, vaccinated patients were 59 percent less likely to be admitted to the ICU than those who had not been vaccinated. Among adults in the ICU with flu, vaccinated patients on average spent 4 fewer days in the hospital than those who were not vaccinated.
  • Flu vaccination can reduce the risk of flu-associated hospitalization.
    • Flu vaccination prevents tens of thousands of hospitalizations each year. For example, during 2019-2020 flu vaccination prevented an estimated 105,000 flu-related hospitalizations.
    • A 2014 study showed that flu vaccination reduced children's risk of flu-related pediatric intensive care unit (PICU) admission by 74 percent during flu seasons from 2010-2012. A 2017 study found that during 2009-2016, flu vaccines reduced the risk of flu-associated hospitalization among older adults by about 40 percent on average.
    • A 2018 study showed that from 2012 to 2015, flu vaccination among adults reduced the risk of being admitted to an intensive care unit (ICU) with flu by 82 percent.
  • Flu vaccination is an important preventive tool for people with certain chronic health conditions.
    • Flu vaccination has been associated with lower rates of some cardiac events among people with heart disease, especially among those who have had a cardiac event in the past year.
    • Flu vaccination can reduce the risk of a flu-related worsening of chronic lung disease (for example, chronic obstructive pulmonary disease (COPD) requiring hospitalization.
    • Among people with diabetes and chronic lung disease, flu vaccination also has been shown in separate studies to be associated with reduced hospitalizations from a worsening of their chronic condition.
  • Flu vaccination helps protect pregnant people during and after pregnancy.
    • Vaccination reduces the risk of flu-associated acute respiratory infection in pregnant people by about one-half.
    • A 2018 study showed that getting a flu shot reduced a pregnant person's risk of being hospitalized with flu by an average of 40 percent from 2010-2016.
    • A number of studies have shown that in addition to helping to protect pregnant people from flu, a flu vaccine given during pregnancy helps protect the baby from flu for several months after birth, when he or she is too young to be vaccinated.
  • Flu vaccine can be lifesaving in children.
    • A 2017 study was the first of its kind to show that flu vaccination can significantly reduce a child's risk of dying from flu.
    • Getting vaccinated yourself may also protect people around you, including those who are more vulnerable to serious flu illness, like babies and young children, older people, and people with certain chronic health conditions.